Field
Embodiments of the present disclosure generally relate to the fabrication of integrated circuits and particularly to patterning hardmask materials, such as amorphous carbon.
Description of the Related Art
Development of etch selective hardmask materials is an important task for patterning new generation NAND (negative-AND) and DRAM (dynamic random-access memory) devices. Carbon-based materials, such as amorphous carbon (denoted as a-C), has been proved to be an effective material serving as etch hardmask for silicon oxide, silicon nitride, poly-crystalline silicon, or metal (e.g., aluminum) materials due to its chemical inertness, optical transparency, and good mechanical properties. During fabrication, an additional mask layer, such as silicon oxide, silicon nitride, or energy sensitive layer, may be used to pattern the hardmask layer.
However, poor adhesion has been observed between the amorphous carbon hardmask layer and the additional mask layer, such as a silicon oxide layer. The poor adhesion may result in undesired particle problems or low quality patterning.
Therefore, there is a need in the art for improving adhesion between a hardmask layer and a subsequent layer.